Gradation Representing Method And Gradation Printer Matter

Abstract

A gradation representing method capable of representing a wide range of high-quality gradation is provided. A gradation representing method of a predetermined unit region 1 by changing area ratio of ink to be recorded in the unit region 1, wherein the gradation of the unit region 1 is represented by recording a first ink recorded at an area ratio of almost 100% in the unit region and a second ink with changing area ratio are recorded overlappedly in the unit region 1.

1 . A gradation representing method of a predetermined unit region by changing area ratio of ink to be recorded in the unit region, wherein 
 the gradation of the unit region is represented by recording a first ink recorded at an area ratio of almost 100% in the unit region and a second ink with changing area ratio are recorded overlappedly in the unit region.    
   
   
       2 . The gradation representing method according to  claim 1 , wherein the first ink and the second ink are similar colors and transmission density of the first ink is different from transmission density of the second ink.  
   
   
       3 . The gradation representing method according to  claim 1 , wherein 
 the area ratio of the second ink changes within a range from 0% to 90%.    
   
   
       4 . The gradation representing method according to  claim 3 , wherein 
 the gradation of the unit region comprises a low density part, a middle density part and a high density part in order of increasing density,    the gradation in the low density part is represented by changing area ratio of a low density ink having comparatively lower density among the different density inks,    the gradation in the middle density part is represented by employing the low density ink as the first ink and employing a high density ink having comparatively higher density as the second ink,    the gradation in the high density part is represented by employing the high density ink as the first ink and the low density ink as the second ink.    
   
   
       5 . The representing gradation method according to  claim 4 , wherein 
 the first ink and the second ink are employed so that gradation at each boundary between the low density part, the middle density part, and the high density part changes in a predetermined range.    
   
   
       6 . A gradation printed matter where gradation of a predetermined unit region is represented by changing area ratio of ink printed in the unit region, wherein 
 the gradation of the unit region is represented by printing a first ink at an area ratio of almost 100% and a second ink with changing area ratio are printed overlappedly in the unit region.    
   
   
       7 . The gradation representing method according to  claim 2 , wherein 
 the area ratio of the second ink changes within a range from 0% to 90%.